minihf.hamiltonian.integral.overlap module

class minihf.hamiltonian.integral.overlap.Overlap[source]

Bases: object

The Obara-Saika scheme for overlap integral.

contracted(self, cga, cgb)[source]: Evaluate integral over contracted GTOs.

primitive(self, pga, pgb)[source]: Evaluate integral over primitive GTOs.

S1d(self, r, pga, pgb)[source]: Obtain the target integral in the Obara-Saika recurrence relations.

contracted(cga, cgb)[source]

Evaluate integral over contracted GTOs.

Parameters:

cga (ContractedGaussian) – The first contracted gaussian orbital.
cgb (ContractedGaussian) – The second contracted gaussian orbital.

Returns:

result – Integral value.

Return type:

primitive(pga, pgb)[source]

Evaluate integral over primitive gaussian orbitals.

Parameters:

pga (PrimitiveGaussian) – The first primitive gaussian orbital.
pgb (PrimitiveGaussian) – The second primitive gaussian orbital.

Returns:

result – Integral value.

Return type:

S1d(A, i, a, B, j, b)[source]

Obtain the target integral in the Obara-Saika recurrence relations.

Parameters:

A (float) – Origin of the basis for one direction.
i (int) – Angular momentum for one direction.
a (float) – Primitive Gaussian exponent for one direction.
B (float) – Origin of the basis for one direction.
j (int) – Angular momentum for one direction.
b (float) – Primitive Gaussian exponent for one direction.

Returns:

result – Integral value for one direction.

Return type: